The present invention relates generally to the field of disc drive data storage devices, and more particularly but not by way of limitation, to the placement of a disc separator having an air dam adjacent a rotatable, rigid disc of a disc drive to reduce and direct air flow generated by rotation of the disc to improve operational performance of the drive.
Modern disc drives are commonly used in a multitude of computer environments to store large amounts of data in a form that is readily available to an end user. A typical disc drive has one or more rigid magnetic recording discs that are rotated by a spindle motor at a constant high speed.
Each disc has a data storage surface divided into a series of generally concentric data tracks radially spaced across a band having an inner diameter and an outer diameter. Data are stored within the data tracks on the disc surfaces in the form of magnetic flux transitions. The flux transitions are induced by an array of read/write heads. Each data track is divided into a number of data sectors where data are stored in fixed size data blocks.
The read/write heads are supported by flexible suspension assemblies which in turn are supported by rigid actuator arms that project into the disc stack. Each head includes an air bearing surface that, in response to air currents caused by rotation of the disc, causes the head to fly adjacent to the disc surface.
A continuing trend in the industry is the simultaneous reduction in size and increase in data storage capacity and processing speed of modern disc drives. Such improvements have been brought about through a variety of changes in the configurations of the drives, including the use of higher disc rotational speeds. While advantageously reducing latency times (i.e., time spent waiting for a selected data block to reach the head as a particular disc rotates), higher rotational speeds tend to induce a greater degree of turbulence in the airflow established by the rotating discs.
Turbulence, or turbulent flow, is characterized by random fluctuations in the speed and direction of the airflow. Such turbulence can cause unwanted vibration of the discs and heads, leading to undesired head position (run-out) error during operation. Accordingly, a need exists within the art to reduce turbulence in the airflow near a disc drive head to reduce run-out errors within the drive.
In accordance with preferred embodiments, a disc drive is provided with at least one rigid, rotatable disc having a disc recording surface and a rotatable actuator assembly which supports a head adjacent the disc recording surface. A stationary disc separator plate is supported adjacent the disc and extends proximate a substantial portion of the disc recording surface. The plate includes a leading edge and a trailing edge which cooperate to form an open portion to provide clearance for the movement of the head. The leading edge is disposed downstream from the head and the trailing edge is disposed upstream from the head.
Preferably, the trailing edge of the plate includes an air dam which diverts a substantial portion of the airflow away from the head, thereby reducing turbulent flow at the head. In a preferred embodiment, the leading edge is provided with a tapered configuration, although in another preferred embodiment the leading edge is provided with a second air dam to further divert airflow away from the open portion near the head. Shroud portions which laterally extend from edges of the plate assist in the direction of the airflow along a desired path.
Preferably, the stationary plate radially extends from close proximity to a spindle motor used to rotate the disc to a disc stack assembly, upon which the discs are secured, past the outer perimeter of the discs. The stationary plate is secured to the basedeck through a tab portion of the stationary plate engaging a notched groove in the basedeck. The stationary plate preferably has sufficient stiffness such that the stationary plate is only supported at the outermost diameter. In drives having multiple discs, a stationary plate is preferably disposed between each adjacent pair of the discs. Additional stationary plates can be provided above the topmost disc and/or below the bottommost disc, as desired.
In still other preferred embodiments, the stationary plate has airflow vents defined in the plate. The number and size of the vents are selected to reduce aerodynamic drag and thereby reduce power consumption requirements of the spindle motor.
These and various other features and advantages which characterize the claimed invention will be apparent upon reading the following detailed description and upon review of the associated drawings.